A small-sized electronic device such as a personal computer (hereinafter referred to as a PC) may be attached to a display. On the backside of the display, a mount that attaches a stand or supporting column thereto is provided. It is difficult to directly attach the PC to the display, and hence a holder to which the PC is attached or in which the PC is stored may be attached to the mount. In general, the number of types of interface ports for electrical connection of a small-sized PC to an external device is small, and hence a port expansion adaptor that expands the types of interfaces may be electrically connected to a small-sized PC. However, there is no useful means for collectively attaching these devices to the display.
A conventional holder that attaches an electronic device such as a PC or the like to the display cannot collectively attach another electronic device required to use the small-sized PC such as a port expansion adaptor or the like in addition to the electronic device such as the small-sized PC.